SiGe Mixers Suit Base Stations From 700 To 4000 MHz

DESIGNED USING A PROPRIETARY silicon-germanium (SiGe) process, a new line of mixers provides input thirdorder intercept point performance to +24.8 dBm. With 2RF-2LO spurious rejection to -79 dBc, these monolithic devices can ease the filtering requirements of close-in harmonics. In addition, conversion gain to 9 dB enables the elimination of a complete intermediate-frequency (IF) amplifier stage within the receiver lineup. Noise-figure values range down to 9 dB. The MAX19995/MAX19995A/ MAX19997A/MAX19999 integrate two mixer cores, four amplifiers, three baluns, a local-oscillator (LO) splitter, and discrete components. The product family also supports two "green" power modes in which linearity performance can be traded for reduced power consumption. In 5-V mode, for example, the bias currents that drive the on-chip LO buffer and IF amplifier stages can be reduced by as much as 33 percent. Using this mode of operation, a 20-percent reduction in power results in only a 3-dB reduction in linearity. P&A: starting at $9.96; qty. 1000.